Mariana Resources Ltd.
TSX : MRY
AIM : MARL
PLUS : MARL

Mariana Resources Ltd.

December 13, 2011 08:00 ET

Mariana Resources Intersects High-Grade Gold and Silver at Sierra Blanca Project, Deseado Massif, Southern Argentina

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Dec. 13, 2011) - Mariana Resources Ltd (TSX:MRY)(AIM:MARL)(PLUS:MARL) ('Mariana' or 'the Company'), the AIM and TSX quoted exploration and development company focused on Argentina and Chile, is pleased to report first assay results received from the initial eight holes of the Phase IV drilling campaign at the Sierra Blanca gold-silver project in the Deseado Massif of southern Argentina.

Highlights

  • High grade gold ('Au') and silver ('Ag') in oxidised sulfide breccias discovered at Vetarron Norte target - associated with multiple sulfide-rich vein breccias hosted by andesites, mafic volcanics and rhyolite dykes over a 250m strike and open in all directions.
  • Best Vetarron Norte target intersections:
    • 15m @ 0.3 g/t Au & 0.7 g/t Ag from 22.5m (VND100)
    • 4.0m @ 3.8 g/t AuEq (2.2 g/t Au & 93 g/t Ag) from 85.5m, including 0.5m @ 24.3 g/t AuEq (12.1 g/t Au & 732 g/t Ag), from 87m (VND102)
  • Vetarron Norte target is part of a robust north-south trending vein-breccia system that extends over a 1.8 km strike in the south-western portion of the project property.
  • Wide zones of low grade silver mineralisation intersected at Lucila target in the hanging wall of the main Lucila vein zone.
    • First step out drillhole LUD103 assayed 22m @ 15.9 g/t Ag from 99m, incl. 0.5m @ 228 g/t Ag from 115.65m and 30.6m @ 20 g/t Ag from 196m.
  • Lucila vein extends ENE-WSW for 1.7 km and forms part of a 5.3 km magnetic low trend which includes the previously untested Trafwe target (drill results pending).
  • Lucila vein drilling to-date has been wide spaced and to a vertical depth of 200m with silver mineralisation open in all directions.

Executive Chairman John Horsburgh said, "These initial results from the latest campaign at Sierra Blanca are highly encouraging and indicate significant potential for multiple mineralised systems at Vetarron and Lucila which are more extensive at depth than is indicated at surface in outcrop and trench sampling. The first high grade gold and silver mineralisation intersected at Vetarron is promising, and while these initial assay results represent only a quarter of the holes that have been drilled, there is already ample scope for follow up drilling in 2012. This latest 5,276m drilling campaign is now complete with final samples being processed for analysis which we look forward to reporting on in due course."

Vetarron Norte

The Vetarron Norte target is located in the southern sector of the Sierra Blanca property and comprises multiple sulfide rich vein breccias zones along a north trending belt 1.8 km long and more than 25m wide. Several low gold and silver anomalies have been detected at surface along this trend with gold up to 0.3 g/t and silver up to 23 g/t in rock chips.

The target is a chargeability anomaly interpreted to be sulphide zones at depth, below outcrop and float of oxidised sulfidic breccias and extensive barren ash cover. All holes targeting the NS trend intersected quartz-sulfide breccias and stockwork up to 50m wide, with strongly anomalous gold (e.g. VND100 15m @ 0.3 g/t Au from 22.5m). In hole VN102, limonitic breccias (oxidised quartz-sulphide vein breccias) were intersected with 16m @ 0.3 g/t Au from 23m and a well-defined oxidised breccia assaying 0.5m @ 12.1 g/t Au and 732 g/t Ag within 4.0m @ 2.2 g/t Au and 93 g/t Ag about 86m below a low grade outcrop (see Figure 4 - http://marianaresources.com/pdf/2011/111213_Mariana_news.pdf).

Lucila Vein Zone

The 1.8 km long Lucila vein is emplaced along a 5.3 km ENE trending magnetic low which includes the untested Trafwe target.

Silver mineralisation is accompanied by significant sulfides (up to 10% pyrite, sphalerite and galena) occurring in quartz-adularia and carbonate veinlets. The mineralisation system at Lucila is composed of a tectonic-hydrothermal breccia up to 15m wide that dips steeply to the north and a wide hanging wall zone of multiple centimetre scale quartz-adularia-sulfide veins. These "hanging wall veins" are interpreted to extend over widths of up to 100m, with a WNW strike and steep northerly dip.

Lucila was tested in 2008 by six shallow RC holes about 300m apart, that intercepted silicified rocks up to 30m wide and quartz-chalcedony veins at depths of 30m-45m below surface with intersections of low grade silver mineralisation, such as 29m @ 0.1 g/t Au and 14 g/t Ag from 27m (SBR33), 6m @ 0.2 g/t Au and 48 g/t Ag from 38m (SBR34) and 3m @ 0.1 g/t Au and 89 g/t Ag from 51m (SBR35). Deeper 2008 reverse circulation/diamond holes intercepted 23.5m @ 0.1 g/t Au and 40 g/t Ag from 90m (SBRD53), and high grade silver intercept of 0.6m @ 359 g/t Ag from 84.75m (SBD 01).

The step-out hole at Lucila LUD103 intersected wide zones of hanging wall stockwork veinlets from 90m below surface and contrasting with the shallow holes, the main breccia zone is widely mineralised assaying 30m @ 0.1 g/t Au and 20 g/t Ag (see Figures 5&6 - http://marianaresources.com/pdf/2011/111213_Mariana_news.pdf).

Summary of Q4 drilling results from Veterron Norte and Lucila

HOLE FROM
(m)
TO
(m)
CORE LENGTH (m) GOLD
(g/t)
SILVER
(g/t)
GOLD
Eq*
TARGET
VND96 17.0 21.0 4.0 0.40 2.0 0.5 Vetarron Norte
And 61.5 68.5 7.0 0.10 5.3 0.2 Vetarron Norte
VND97 No Vein breccia intersected Vetarron Norte
VND98 No Vein breccia intersected Vetarron Norte
VND99 No Vein breccia intersected Vetarron Norte
VND100 22.5 37.5 15.0 0.30 0.7 0.3 Vetarron Norte
and 148.0 149.0 1.0 1.20 76.6 2.5
VND101 63.0 67.0 4.0 0.70 1.2 0.7 Vetarron Norte
and 107.5 109.5 2.0 0.60 0.5 0.6 Vetarron Norte
VND102 23.0 39.0 16.0 0.30 1.8 0.3 Vetarron Norte
and 85.5 90.0 4.5 2.20 92.8 3.8
incl 87.0 87.5 0.5 12.10 732.0 24.3
LUD103 99.0 121.0 22.0 0.05 15.9 0.3 Lucila
incl 115.6 116.1 0.5 0.10 228.0 3.9
and 159.5 164.9 5.3 0.00 11.4 0.2
and 196.4 227.0 30.6 0.10 20.0 0.4

Gold equivalent grade is calculated by dividing silver assays by 60 and adding to the gold value and this assumes 100% metallurgical recovery. True widths are estimated to be 85-90% of the stated interval.

Sierra Blanca Background

The 7,000 Ha Sierra Blanca Project is located 50km NW of AngloGold Ashanti's Cerro Vanguardia mine along the Tranquilo regional fault system and is adjacent to TSX quoted Argentex Mining's Pinguino epithermal gold-silver/polymetallic discovery (Figure 1). Sierra Blanca was part of the Santa Cruz Joint Venture with IAMGOLD Corporation. However Mariana has exercised its option to acquire IAMGOLD's 30% by paying US$500,000 cash and issuing Mariana shares to the value of US$500,000 and now holds 100% of the Project.

Mariana discovered epithermal gold-silver mineralisation at the Veta Chala target in 2008. Drilling was limited to 17 reverse circulation and six diamond holes totaling 1,750m, targeting veins and breccias exposed in trenches from which numerous bonanza and high grade assays were obtained in channel sampling (see news release 02/04/08). Several of these holes were rendered ineffective because of poor diamond core recovery or high water flow in RC holes. 3-D IP, LAG sampling and ground magnetic surveys preceded the recent programme. Chala-Achen is one of several epithermal gold-silver prospects and numerous under-explored veins located within the property. Sierra Blanca has both low and intermediate style sulphidation epithermal mineralisation.

ADDITIONAL INFORMATION

The Phase IV drilling programme was undertaken by ECOMINERA. The Company's Vice-President Exploration, Dr Gustavo Rodriguez (MAIG), directed the drill programme under the supervision of Executive Chairman Mr John Horsburgh. Exploration information in this announcement has been compiled by John Horsburgh who is a Fellow of the Australasian Institute of Mining and Metallurgy. Mr Horsburgh has sufficient experience relevant to the style of mineralization and types of gold deposit under consideration and to the activity that he is undertaking to qualify as a Competent Person as defined in the JORC Code. Mr Horsburgh is a Qualified Person within the meaning of National Instrument 43-101.

Quality Assurance/Quality Control

All technical information for the Company's Argentina projects is obtained and reported under a quality assurance and quality control (QA/QC) program. All samples are collected under the supervision of the Company geologists and dispatched via commercial transport to ALS Chemex laboratories in Mendoza, Argentina, and assayed in Chile. ALS Chemex's quality system complies with the requirements for the International Standards ISO 9001:2000 and ISO 17025: 1999. Samples returning greater than 10 g/t gold and/or greater than 100 g/t silver are assayed using gravimetric analyses.

Systematic assaying of sample duplicates and commercially prepared standards and blanks is performed for analytical reliability.

For further information please visit website at www.marianaresources.com.

About Mariana Resources

Mariana Resources Ltd is an AIM and TSX quoted exploration and development company with an extensive portfolio of gold, silver and copper projects in Argentina and Chile. In southern Argentina, in addition to the Las Calandrias gold-silver discovery, the Company has the Sierra Blanca silver-gold prospect (100%); the Los Amigos joint venture (49%) with Hochschild Mining and a 220,000 Ha land package (100%) in the country. All of these projects are located in the Deseado Massif epithermal gold-silver district in mining-friendly Santa Cruz province of southern Argentina, which hosts four mines and several advanced projects. In Chile, Mariana has a joint venture with US based international mining and natural resources company Cliffs Natural Resources Inc., to explore for iron oxide-copper-gold deposits ('IOCG') in a 92,000 km² area ("SCM Mariana Area") in north-central Chile along the highly prospective Atacama Fault Zone. The SCM Mariana Area includes the 44km² Buenaventura and 46km² Perro Chico IOCG projects. Mariana is also evaluating a number of gold-silver and copper-gold opportunities away from the Cliffs JV area, as part of a new initiative.

Safe Harbour

This press release presents "forward-looking statements" within the meaning of Canadian securities legislation that involve inherent risks and uncertainties. Forward-looking statements include, but are not limited to, statements with respect to the future price of gold and other minerals and metals, the estimation of mineral resources, the capital expenditures, costs and timing of the resources, the realization of mineral reserve estimates, the capital expenditures, costs and timing of the development of new deposits, success of exploration activities, permitting time lines, currency exchange rate fluctuations, requirements for additional capital, government regulation of mining operations, environmental risks, unanticipated reclamation expenses, title disputes or claims and limitations on insurance coverage. Generally, these forward-looking statements can be identified by the use of forward looking terminology such as "plans", "expects" or "does not expect", "is expected", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does not anticipate", or "believes", or variations of such words and phrases or state that certain actions, events or results "may", "could", "would", "might" or "will be taken", "occur" or "be achieved".

Forward-looking statements are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Mariana to be materially different from those expressed or implied by such forward looking statements, including but not limited to: risks related to international operations, actual results of current exploration activities; actual results of current or future reclamation activities; conclusions of economic evaluations; changes in project parameters as plans continue to be refined; future prices of gold and other minerals and metals; possible variations in ore reserves, grade or recovery rates; failure of equipment or processes to operate as anticipated; accidents, labour disputes and other risks of the mining industry; and delays in obtaining governmental approvals or financing or in the completion of development or construction activities. Although the management of Mariana believes that the expectations reflected in such forward-looking statements are based upon reasonable assumptions and have attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Mariana Resources does not undertake to update any forward-looking statements that are incorporated by reference herein, except in accordance with applicable securities laws.

NEITHER THE TSX NOR ITS REGULATION SERVICES PROVIDER (AS THAT TERM IS DEFINED IN THE POLICIES OF THE TSX EXCHANGE) ACCEPTS RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THIS NEWS RELEASE

Contact Information

  • In Australia:
    Mariana Resources Ltd
    John Horsburgh (Chairman)
    +61 2 94374588

    Mariana Resources Ltd
    Glen Parsons (CFO)
    +61 2 94374588

    RFC Corporate Finance Limited (Nomad)
    Rob Adamson
    +61 2 9250 0041

    RFC Corporate Finance Limited (Nomad)
    Will Souter
    +61 2 9250 0050

    In U.K.:
    FinnCap (Broker)
    Matthew Robinson
    +44 20 7600 1658

    Fox Davies Capital (Co UK Broker)
    Jonathan Evans
    +44 20 3463 5000

    St Brides Media and Finance Ltd (PR)
    Felicity Edwards
    +44 20 7236 1177

    In Canada:
    Mariana Resources Ltd (Vancouver Office)
    Kathryn Witter
    +1 604 669 9336
    www.marianaresources.com

    Renmark Financial Communications (PR)
    Arash Shahi
    +1 514 939 3989

    Renmark Financial Communications (PR)
    Philip Robin
    +1 416 644 2020